Claims
- 1. A method for removing nitrate or nitrite ions from a waste solution comprising the following steps:
- Step 1 - providing a waste solution comprising water and nitrate or nitrite ions and having a surface, a source of heat generating heat, and a catalyst;
- Step 2 - submerging said source of heat generating said heat and said catalyst below said surface of said waste solution, said catalyst being located in close proximity to said heat source, said heat having a temperature sufficiently high to decompose nitrate or nitrite ions contained in said waste solution, said heat source and said catalyst being located sufficiently below said surface of said waste solution to provide a sufficient residence time for gases formed by heating of said waste solution by said heat from said heat source to be sufficiently contacted by said waste solution to remove essentially all volatile waste solution soluble species and to remove essentially all particles present in said gases formed by said heat from said heat source before said gases reach said surface of said waste solution; and
- Step 3 - maintaining said heat source generating said heat and catalyst below said surface of said waste solution for a period of time sufficient to decompose said nitrate or nitrite ions.
- 2. A method in accordance with claim 1 wherein said flame temperature is equal to or greater than the temperature required to decompose said nitrate or nitrite ions in said waste solution.
- 3. A method in accordance with claim 1 wherein said period of time in Step 3 is equal to or greater than the time required to decompose said nitrate or nitrite ions in said waste solution.
- 4. A method in accordance with claim 1 wherein said heat source comprises a submergible torch.
- 5. A method in accordance with claim 1 wherein said heat source comprises an ion plasma.
- 6. A method in accordance with claim 1 wherein said heat source comprises an electric arc.
- 7. A method in accordance with claim 1 wherein said catalyst comprises platinum black.
- 8. A method for removing nitrate or nitrite ions from a waste solution comprising the following steps:
- Step 1 - providing a waste solution comprising water and nitrate or nitrite ions and having a surface;
- Step 2 - igniting a fuel of a submergible torch to produce a flame;
- Step 3 - submerging said submergible torch below said surface of said waste solution, said submergible torch comprising a combustion chamber having an open end and containing said flame, a catalyst being connected to said combustion chamber by a support in close proximity to said flame, said flame contacting said surface of said waste solution at said open end of said combustion chamber, said flame having a flame temperature sufficient to decompose said nitrate or nitrite ions in said waste solution, said submergible torch being located sufficiently below said surface of said waste solution to provide a sufficient residence time for gases formed by heating of said waste solution by said flame to be sufficiently contacted by said waste solution to remove essentially all volatile waste solution soluble species and to remove essentially all particles present in said gases formed by heating of said waste solution by said flame before said gases reach said surface of said waste solution; and
- Step 4 - maintaining said submergible torch below said surface of said waste solution for a period of time sufficient to decompose said nitrate or nitrite ions.
- 9. A method in accordance with claim 8 wherein said flame temperature is equal to or greater than the temperature required to decompose said nitrate or nitrite ions in said waste solution.
- 10. A method in accordance with claim 8 wherein said period of time in Step 4 is equal to or greater than the time required to decompose said nitrate or nitrite ions in said waste solution.
- 11. A method in accordance with claim 8 wherein said fuel comprises a mixture of an oxygen containing gas and a hydrogen containing gas selected from the group consisting of acetylene, propane, hydrogen, propylene, and mixtures thereof.
- 12. A method in accordance with claim 8 wherein said catalyst comprises platinum black.
Parent Case Info
This application is a division of application No. 07/924,206, filed Aug. 3, 1992, abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (1)
Number |
Date |
Country |
62-11320 |
Mar 1987 |
JPX |
Non-Patent Literature Citations (2)
Entry |
Thompson et al, "Fluidized Bed Calcination of Radioactive Wastes Using In-Bed Combustion Heating", Nuclear Technology, vol. 16, Nov. 1972 pp. 396-405. |
Stinson, Stephen C., "EPA to Evaluate New Technologies For Cleaning Up Hazardous Wastes", Chemical and Engineering News, May 25, 1987, pp. 7-12. |
Divisions (1)
|
Number |
Date |
Country |
Parent |
924206 |
Aug 1992 |
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